Electronics Setup
After assembling the MAG-BOARD hardware, several user interface and configuration components must be connected. These components allow the user to control the gradiometer, view measurements, and optionally store recorded data.
The MAG-BOARD supports connection of buttons, LEDs, an LCD display, and optional external flash memory.
Buttons
The MAG-BOARD allows connection of up to three control buttons.
These buttons provide basic control of the gradiometer during operation.
| Button | Function |
|---|---|
| NULL | Zero calibration of the gradiometer |
| + | Increase measurement sensitivity |
| − | Decrease measurement sensitivity |
These buttons connect to the designated pins on the MAG-BOARD and allow quick adjustment of system parameters in the field.
LED Indicators
The board also supports up to two LED indicators.
LEDs can be used to display system status or signal activity.
Typical uses include:
- power indication
- system status
- signal detection feedback
LED polarity must be respected when connecting them to the board.
LCD Display
An optional LCD display module can be connected to the MAG-BOARD to show real-time measurement values.
The display typically shows:
| Label | Description |
|---|---|
| U | Value from the upper sensor |
| L | Value from the lower sensor |
| D | Gradient value between the sensors |
These values allow the user to monitor the gradiometer response during operation and calibration.
LCD Voltage Selection
The MAG-BOARD includes a voltage selection jumper for the LCD display.
Default configuration: If the LCD display is supplied with the MAG-BOARD kit, no modification is required.
Using a 3.3 V LCD display: If a 3.3 V LCD module is used, the voltage jumper must be modified:
- Locate the LCD voltage selection jumper on the board
- Cut the default connection
- Bridge the 3.3 V pad with a small amount of solder
This ensures the LCD operates with the correct voltage level.
External Flash Memory (Optional)
The MAG-BOARD includes pads for installing external SPI flash memory.
This memory can be used to store measurement data directly on the board.
Recommended chip: W25Q32JVSS
Other compatible SPI flash memory devices may also work. The chip must be soldered carefully to the designated footprint on the board.
Verifying the Setup
Before continuing to firmware programming, verify the following:
- buttons are correctly connected
- LEDs are installed with correct polarity
- LCD display is connected properly
- LCD voltage jumper matches the display voltage
- optional flash memory is installed correctly (if used)
After completing the electronics setup, continue with: